CRTblDesc (table descriptor)

DbiDoRestructure and DbiCreateTable both use the CRTblDesc structure, but the way they use the structure is quite different. Some of the fields within CRTblDesc are not specified at create time for use with DbiCreateTable; they are specified only with DbiDoRestructure to modify the table.

CRTblDesc for creating a table

The CRTblDesc structure defines the general attributes of the table and supplies pointers to arrays of field, index, and other descriptors. The following CRTblDesc structure defines the table structure:

Field	Type	Description
szTblName	DBITBLNAME	Specifies the table name, including optional path and extension.
szTblType	DBINAME	Specifies the driver type.
szErrTblName	DBIPATH	Reserved.
szUserName	DBINAME	Reserved.
szPassword	DBINAME	Specifies the master password (if bProtected is TRUE). (Paradox only.)
bProtected	BOOL	TRUE if encryption is desired (Paradox only).
iFldCount	UINT16	Specifies the number of field definitions supplied.
pfldDesc	pFLDDesc	Specifies the array of field descriptors.
iIdxCount	UINT16	Specifies the number of index definitions supplied.
pidxDesc	pIDXDesc	Specifies the array of index descriptors.
iSecRecCount	UINT16	Specifies the number of security definitions given (Paradox only).
psecDesc	pSECDesc	Specifies the array of security descriptors (Paradox only).
iValChkCount	UINT16	Specifies the number of validity checks (Paradox and SQL only).
pvchkDesc	pVCHKDesc	Specifies the array of validity check descriptors (Paradox and SQL only).
iRintCount	UINT16	Specifies the number of referential integrity specifications (Paradox and SQL only).
printDesc	pRINTDesc	Specifies the array of referential integrity specifications (Paradox, dBASE and SQL only).
iOptParams	UINT16	Specifies the number of optional parameters.
pfldOptParams	pFLDDesc	Specifies the array of field descriptors for optional parameters.
pOptData	pBYTE	Specifies the values of optional parameters.

CRTblDesc for restructuring a table

A complete description of CRTblDesc, as used to restructure a table is described below.

Type		Name	Description
DBITBLNAME		szTblName	Required; specifies the source table name. The table name can contain an extension.
DBINAME		szTblType	If specified, it must match the driver type associated with the source table.
DBIPATH		szErrTblName	Not currently used.
DBINAME		szUserName	Not currently used.
DBINAME		szPassword	Optional; if bProtected is set to TRUE, specifies the password of the destination table.
BOOL		bProtected	Optional; If TRUE, specifies that a master password is supplied for the destination table. Paradox only.
BOOL		bPack	Optional; If TRUE, specifies packing for restructure.
(iFldCount, pecrFldOp, and pfldDesc are required to describe the new record structure)
UINT16		iFldCount	Optional; used if the record structure is changing. Specifies the number of field operators and field descriptors passed in pecrFldOp and pFldDesc for the new record structure.
pCROpType		pecrFldOp*	Optional; pointer to an array of CROpType structures, one for each field in the record; used if the record structure is changing, it indicates how the fields are rearranged. For each changed field, set it to crADD if the field is added, crMODIFY if the field is modified, or crCOPY if the field is moved.
pFLDDesc		pfldDesc	Optional; used if the record structure is changing. Specifies an array of physical field descriptors for the new record structure. ifldNum in each pfldDesc must be 0 if the field is added. Otherwise, it must contain the field position (1 to n) in the old record structures. If a field is dropped, its descriptor is simply left out of the new record structure. Additionally, any changes to dependent objects are made automatically (that is, all single field indexes, validity checks, and auxiliary passwords are dropped).
(For all the following objects, only the changes must be input.)
UINT16		IdxCount	Optional; specifies the number of index operators and index descriptors passed in pIdxDesc.
pCROpType		pecrIdxOp	Optional; to change an index, specify crADD, crMODIFY, crREDO, or crDROP.
pIDXDesc		pidxDesc	Optional; specifies an array of index descriptors.
UINT16		iSecRecCount	Optional; for Paradox only; specifies the number of security definitions passed in psecDesc.
pCROpType		pecrSecOp	Optional; to change a security definition, specify crADD, crMODIFY, or crDROP.
pSECDesc		psecDesc	Optional; for Paradox only; specifies an array of security descriptors.
UINT16		iValChkCount	Optional; for Paradox only; specifies the number of validity checks passed in pecrValChkOp and pvchkDesc.
pCROpType		pecrValChkOp	Optional; for Paradox only; to change a validity check, specify crADD, crMODIFY, or crDROP.
pVCHKDesc		pvchkDesc	Optional; for Paradox only; specifies an array of validity check descriptors.
UINT16		iRintCount	Optional; for Paradox only; specifies the number of referential integrity operators passed in printDesc.
pCROpType		pecrRintOp	Optional; for Paradox only; to change a referential integrity operator, specify crADD, crMODIFY, or crDROP. crMODIFY cannot be used to change the name of a referential integrity constraint. To modify the name, use crDROP and crADD.
pRINTDesc		printDesc	Optional; for Paradox only; specifies an array of referential integrity specifications.
UINT16		iOptParams	Optional; specifies the number of optional parameters (for example, language driver information).
pFLDDesc		pfldOptParams	Optional; specifies an array of field descriptors for optional parameters.
pBYTE	pOptData		Optional; specifies values of optional parameters.

Operands for table restructure

The following operation types are valid only for restructuring the table:

Operation type	Value	Description
crNOOP	0	Perform no operation
crADD	1	Add a new element
crCOPY	2	Copy an existing element
crMODIFY	3	Modify an element
crDROP	4	Removes an element